Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Dans ce travail de thèse, nous nous sommes intéressés aux rôles de l’hypoxie intermittente (HI) sur l’inflammation respiratoire. Dans un premier travail, nous avons caractérisé le profil inflammatoire des cellules épithéliales nasales humaines (CENH) en réponse à l’HI et mis en évidence une augmentation significative de la sécrétion d’IL-8, de PDGF AA, de VEGF et de gélatinases. L’IL-8 sécrétée était active comme en atteste le pouvoir chémotactique majeur des surnageants de CENH envers les neutrophiles. De plus, nous avons montré que l’HI per se était responsable d’une augmentation de la migration des neutrophiles et que l’addition d’IL-8 potentialisait cet effet, d’autant plus qu’elle agissait sur des neutrophiles de patients présentant un syndrome d’apnées/hypopnées du sommeil, déjà activés. Dans le second travail, nous avons mis en évidence une réponse spécifique des cellules musculaires lisses bronchiques à l’HI avec une sécrétion de VEGF et surtout une augmentation de leurs capacités de migration. De surcroît, nous avons montré que le surnageant des CENH soumises à l’HI induisait une augmentation majeure de ces capacités de migration, dépendant de la sécrétion de PDGFAA. Nos études montrent que l’HI induit une réponse inflammatoire des cellules résidentes de l’arbre trachéobronchique, cellules épithéliales et musculaires lisses. L’utilisation d’un modèle in vitro a permis d’isoler cette réponse tissulaire spécifique de l’influence d’une inflammation vasculaire et systémique. Ces résultats peuvent expliquer la neutrophilie observée dans les expectorations des apnéiques ainsi que les résultats fonctionnels respiratoires de ces patients / In present work, we addressed the role of Intermittent Hypoxia (IH) on respiratory inflammation. In a first study, we characterized the inflammatory profile of the human nasal epithelial cells (CENH) in response to IH and showed a significant increase of the IL-8, PDGF AA, VEGF and gelatinases secretion. The released IL-8 was active, as shown by the ability of supernatants to induce neutrophil migration. Furthermore, we showed that IH per se induced neutrophil migration and that IL-8 had an additive effect, especially on already activated neutrophils from patients suffering from sleep apnea/hypopnea syndrome (SAHS). In the second study, we showed a specific response of bronchial smooth muscle cells (BSMC) to IH with induction of VEGF secretion and an increase in migration capacities. In addition, supernatants of CENH exposed to IH induced a major increase of BSMC migration, dependent on PDGFAA secretion. Our studies show that IH leads to an inflammatory response of the resident tracheobronchial cells, both epithelial and smooth muscle cells. The use of an in vitro model allowed to isolate the specific tissular response from the influence of a vascular and systemic inflammation. These results can explain the neutrophilia observed in induced sputum of patients with SAHS, as well as the results of their pulmonary functional tests

Adaptation to chronic hypoxia induces endogenous cardioprotection and increases the heart resistance to ischemia/reperfusion injury. The heart mitochondria, which produce reactive oxygen species (ROS) in addition to ATP, play an important role in these processes. During ischemia/reperfusion, ROS are produced in excessive amounts and damage the cells. However, in lower concentrations, ROS are involved in the signalling pathway of cardioprotection induced by adaptation to chronic hypoxia. In the heart, two mitochondrial subpopulations have been observed, subsarcolemmal mitochondria (SSM) and intermyofibrillar mitochondria (IMFM), which differ in cell localization as well as in morphological and biochemical properties. The aim of this work was to introduce the method of SSM and IMFM isolation in our laboratory and to analyse their antioxidative capacity after adaptation to chronic hypoxia. Adult male Wistar rats were kept either under normoxic conditions or exposed to intermittent high-altitude hypoxia (IHA; 7000 m, 5 days a week/8 hours a day, totally 25 exposures). Mitochondrial subpopulations were isolated from heart left ventricle and their functionality was verified by measuring oxygen consumption and enzyme activities. The IMFM had higher oxygen consumption in comparison with SSM and activities...

O objetivo do presente estudo foi analisar o efeito da suplementação de creatina sobre o desempenho físico de adultos jovens treinados submetidos a esforços intermitentes máximos no cicloergômetro. A amostra foi composta por 26 indivíduos saudáveis, do sexo masculino, que foram divididos aleatoriamente em dois grupos, suplementado com creatina (CR, n = 13; 22,5 &#177; 2,7 anos; 74,9 &#177; 6,8 kg; 178,5 &#177; 4,8 cm) e placebo (PL, n = 13; 22,9 &#177; 3,2 anos; 71,9 &#177; 11,3 kg; 178,6 &#177; 4,0 cm). A suplementação de creatina ou placebo (maltodextrina) foi consumida por meio de delineamento duplo cego, em quatro doses de 5 g/dia durante os cinco primeiros dias (20 g/dia). A partir daí, uma única dose de 3 g/dia foi ingerida nos 51 dias subsequentes. Foi realizado um controle prévio dos hábitos alimentares e dos níveis de aptidão física dos indivíduos. Para avaliação do desempenho físico em esforços intermitentes foram realizados três Testes de Wingate (TW), separados por 2 minutos de intervalo, pré e pós-suplementação de CR ou PL. Os índices de desempenho físico analisados foram: potência de pico relativa (PPR); potência relativa a cada período de 5 s (PR); potência média relativa (PMR); trabalho total relativo (TTR) e índice de fadiga (IF). Foram coletados 25 &#181;l de sangue no lóbulo da orelha um minuto após a realização de cada TW para a dosagem de lactato sanguíneo (LAC). Coletas de urina de 24 horas foram utilizadas para a determinar as concentrações de creatinina (CRT) antes e após o período de suplementação. Os dados foram tratados por ANOVA e ANCOVA para medidas repetidas, seguidas pelo teste post hoc de Scheffé. A PPR no TW2 foi significativamente maior (6%) para o grupo CR comparado ao grupo PL após a suplementação (p<0,01). PR no período de 0-5 s no TW2 foi significante maior para o grupo CR (11%) comparado ao PL após a suplementação (p<0,02). A PMR e o IF não apresentaram diferenças significativas nos TW, entre os grupos CR e PL após a suplementação (p>0,05). O TTR foi significativamente maior no grupo CR (3%) comparado ao PL após a suplementação (p<0,02). O LAC não apresentou diferenças significantes nos TW, entre os grupos CR e PL, após suplementação (p>0,05). Interação significante entre grupo e tempo foi encontrada para a CRT, indicando que o grupo CR teve sua taxa de excreção aumentada (22%) após a suplementação de creatina (p<0,03). Os resultados do presente estudo sugerem que a suplementação de creatina melhora o desempenho físico em esforços intermitentes de alta intensidade e curta duração, e que esta melhora parece ser determinada nos 5 s iniciais de esforço. / The objective of present study was to analyze the effect of creatine supplementation on performance of trained young adults submitted the intermittent maximal efforts in cycle ergometer. The sample was composed by 26 individuals healthy, male, that were randomly divided in two groups, supplemented with creatine (CR, n = 13; 22.5 &#177; 2.7 years; 74.9 &#177; 6.8 kg; 178.5 &#177; 4.8 cm) and placebo (PL, n = 13; 22.9 &#177; 3.2 years; 71.9 &#177; 11.3 kg;178.6 &#177; 4.0 cm). The creatine supplementation or placebo (maltodextrin) was consumed through a blind double manner, in four doses 5 g/day during the first five days (20 g/day). Therefore, a single dose 3 g/day was ingested in the following 51 days. Previous control of the alimentary habits was accomplished and levels of physical fitness of the individuals. For evaluation of the performance in intermittent maximal efforts three Wingate Test (WT) were accomplished separate for 2 minutes of interval, pre and pos supplementation of CR or PL. The analysis performance indexes were: relative peak power (RPP), relative power to each period of 5 s (RP), relative mean power (RMP), relative total work (RTW) and index of fatigue (IF). The 25 &#181;l blood were collected in the earlobe one minute after the accomplishment of each TW for the dosage of lactate blood (LAC). Collections of urine of 24 hours were used for the determination of creatinine concentration (CRT) before and after the supplementation period. ANOVA and ANCOVA with repeated measures, followed by the test post hoc from Scheffé. RPP in WT2 was significantly larger (6%) for the group CR compared to the group PL after the supplementation (p<0.01). The PR in period of 0-5 s in TVV2 was significant larger for the group CR (11%) compared to PL after the supplementation (p <0.02). RMP and IF didn\'t present significant differences in WT, among the groups CR and PL after the supplementation (p>0.05). RTW was significantly larger in the group CR (3%) compared to PL after the supplementation (p<0.02). The LAC didn\'t present significant differences in WT, among the groups CR and PL, after supplementation (p>0.05). Significant interaction between group and time was found for CRT, indicating that the group CR had his tax of increased excretion (22%) after the supplemented with creatine (p<0,03). The results of the present study suggest that creatine supplementation improve the performance in intermittent efforts of high intensity and short duration, and this improvement seems to be certain in 5 s initial of effort.

Le présent travail concerne l'étude du décollement de coin de compresseurs par des investigations expérimentaux sur le banc d'essai subsonique grille d'aubes situé au LMFA (Re = 3.8 x 105, M = 0,12, profil NACA 65-009). Habituellement, cette particulière séparation tridimensionnelle a lieu dans le coin entre l'aubage et la paroi du moyeu des rangées d'aubes, également dans les stators et les rotors.Les performances de l’étage sont ainsi dégradées à cause des pertes de charge et du blocage conséquent à la séparation de l’écoulement. Bien que les caractéristiques stationnaires sont bien connues par la littérature, uniquement des récentes études expérimentales avancées combinées aux améliorations de simulations numériques, telles que URANS et LES, ont permis de découvrir le comportement très instable du décollement de coin. Des études préalables sur le même banc d'essai ont rapporté un comportement intermittent du décollement, appelé comportement bimodal. Dans la présente thèse de doctorat, il est montré que le comportement bimodal correspond à deux états spécifiques du champ fluide: une séparation fermée, presque supprimée, et une séparation ouverte caractérisée par un blocage massif. Il est clair que cette commutation bimodale du décollement de coin apparaissant dans une machine réelle pourrait avoir un impact fortement déstabilisant. En utilisant la méthode de mesure PIV haute vitesse couplée à des mesures de pression résolues en temps sur la surface de l'aubage, l'écoulement d'un canal inter-aube a été étudié pour deux différentes incidences. Les mesures PIV fournissent pour la première fois des visualisations résolues en temps et étendues à toute la section de l'aubage de la variation bimodale du décollement. L'interaction des grandes structures aléatoires de la couche limite à l'amont avec le bord d'attaque de l'aubage déstabilise le front du décollement et agrandit la région de recirculation. Une séparation ainsi massive persiste jusqu'à ce que le blocage dans le canal inter-aube provoque la rupture des plus grandes structures constituant la zone de recirculation. Successivement le débit recommence à accélérer et la séparation est presque supprimée. Cette dynamique coïncide avec le régime d'écoulement hautement instationnaire et apériodique des diffuseurs, appelé large transitory stall, caractérisé par des grandes amplitudes d'énergie dans la gamme des basses fréquences du spectre. Des moyennes conditionnelles de pression et la décomposition orthogonale modale (POD) des champs de vitesse ont été appliquées pour montrer l'effet rétroactif du blocage induit par la séparation ouverte sur l'angle local au bord d'attaque. Ces résultats supportent l’hypothèse d'une instabilité auto-entretenue causée par la diffusion imposée dans le stator. En fin, des mesures de pression totale résolues en temps ont été effectuées en utilisant des capteurs à haute réponse en fréquence, situés à la même position dans les différents canaux adjacents. La cohérence et la linéarité de l'angle de phase trouvée entre les capteurs confirment que l'instabilité du décollement peut se propager d'un canal a l'autre, en analogie avec les perturbations tournantes (rotating instabilities) apparaissant dans les bancs d'essai annulaires. Ceci montre pour la première fois que, même dans une grille d'aubes linéaire de compresseur, l'instabilité intrinsèque du décollement de coin peut déclencher la propagation d'instabilités. / The present work focuses on the study of the corner separation phenomenon in compressors carried out by experimental investigations on a subsonic linear cascade test rig (Re=3.8x105, M=0.12, blade profile NACA 65-009). Usually, this particular three-dimensional separation takes place in the corner between the blade and the endwall of compressor rows, mostly at hub, both in stators and rotors.Its main features are high total pressure losses and blockage of the flow, with consequent impacts on the efficiency. Whereas time averaged characteristics are well known from the past, only recent advanced experimental studies and improvements of numerical simulations, such as URANS and LES, have permitted to uncover the highly unsteady behavior of corner separation in compressors. Precedent studies on the same test rig have reported an intermittent unsteady behavior of corner separation, called bimodal behavior. In the present thesis it is shown that the bimodal behavior corresponds to two specific states of the flow: a closed separation, almost suppressed, and an open separation characterized by massive blockage and losses. Clearly hub-separation bimodal switches appearing in a real machine could have a first order detrimental effect on the stability of the flow in the compressor. By using high speed PIV coupled with unsteady pressure measurements on the surface of the blade the flow in a single blade passage has been investigated for different incidences. The PIV measurements provide, for the first time, time-resolved flow visualizations of the size switch of the separation with an extended field of view covering the entire blade section. The interaction of random large structures of the incoming boundary layer with the blade is found to be a predominant element that destabilizes the separation boundary and enlarges the recirculation region. Such a massive separation persists until the blockage in the passage causes the breakdown of the largest structures in the aft part of the blade, reestablishing the closed separation state. Such dynamics coincide with the aperiodic intermittent flow regime of diffusers, called transitory stall regime, and the associated Fourier spectra show the largest energy amplitudes in the low frequency range. Conditional ensemble averages of pressure and proper orthogonal decomposition (POD) of velocity fields have been applied to show the feedback effect of the blockage of the separation on the flow angle around the blade leading edge. These results draw the picture of a self-sustained instability caused by the diffusion imposed by the inter-blade passage. To answer the question about the interaction between adjacent corner separations, time-resolved total pressure measurements have been carried out by using high frequency response sensors positioned in bimodal points of multiple passages. The coherent propagation velocity and the linearity of the phase angle found between the signals confirm that the unsteadiness of the separation can propagate in pitch-wise direction. It is interesting to underline that equivalent elements characterize rotating disturbances appearing in annular test rigs. This finally shows that, even in an isolated stator blade row, the intrinsic unsteadiness of corner separation can start the propagation of instabilities. It is the first time that such a propagation effect is observed in a linear compressor cascade.

Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2018-12-17T11:52:56Z No. of bitstreams: 1 Maria Ivone Fortunato Laraia.pdf: 1689216 bytes, checksum: bb1aff1784125d849eedf26f1a503a17 (MD5) / Made available in DSpace on 2018-12-17T11:52:56Z (GMT). No. of bitstreams: 1 Maria Ivone Fortunato Laraia.pdf: 1689216 bytes, checksum: bb1aff1784125d849eedf26f1a503a17 (MD5) Previous issue date: 2018-12-03 / The intermittent labor contract, provided for in the text of article 452-A of the Consolidation of Labor Laws, a mechanism added by labor reform (Law 13467/17), is a contract in which the rendering of service, with subordination, is not continuous, with periods of actual work and inactivity, and can be determined by hour, day or month of work and without a fixed journey. It was conceived to be one of the solutions found for the serious Brazilian economic crisis, since it aims to create jobs, modernize labor laws and increase the competitiveness of Brazilian companies, facing the demands of contemporary capitalism. The intermittent contract, as it was instituted, breaks with the logic of the standard employment bond and contributes to the precariousness of the employment relations, since it allows the use of labor in a discontinuous way; authorizes the payment of salaries lower than the minimum constitutionally guaranteed; violates the principles of human dignity and the social value of work, improves the social status of the worker and offends the right to paid annual leave, at least one third more than the normal salary of the worker, rendering building a free, fair and supportive society, with the eradication of poverty and the reduction of social inequalities, thus failing to promote the welfare of all. This paper presents a proposal for a bill, inspired by Portuguese and Italian legislation, in order to enable the intermittent employee to carry out fundamental social rights, especially human dignity / O contrato de trabalho intermitente, previsto no texto do artigo 452-A da Consolidação das Leis do Trabalho, dispositivo acrescido pela reforma trabalhista (Lei 13.467/2017), é um contrato em que a prestação de serviço, com subordinação, não é contínua, havendo períodos de efetivo trabalho e de inatividade, podendo ser determinado por hora, dia ou mês de trabalho e sem uma jornada fixa. Foi concebido para ser uma das soluções encontradas para a grave crise econômica brasileira, pois objetiva a criação de empregos, modernização das leis trabalhistas e o aumento da competitividade das empresas brasileiras, diante das exigências do capitalismo contemporâneo. O contrato intermitente, da forma como foi instituído, rompe com a lógica do vínculo de emprego padrão e contribui para a precarização das relações de emprego, pois permite a utilização da mão de obra de forma descontínua; autoriza o pagamento de salários inferiores ao mínimo constitucionalmente assegurado; viola os princípios da dignidade humana e do valor social do trabalho, da melhoria da condição social do trabalhador e ofende o direito do gozo de férias anuais remuneradas, com, pelo menos, um terço a mais do que o salário normal do trabalhador, inviabilizando a construção de uma sociedade livre, justa e solidária, com erradicação da pobreza e redução das desigualdades sociais, deixando, assim, de promover obem de todos. Neste trabalho, apresenta-se uma proposta de projeto de lei, inspirada nalegislação portuguesa e na italiana, com a finalidade de possibilitar ao empregado intermitente a efetivação dos direitos fundamentais sociais, especialmente a dignidade humana

O objetivo deste trabalho é apresentar o teste de esforço com o dinamômetro isocinético na avaliação objetiva da isquemia funcional da doença arterial oclusiva de membros superiores (DAOMS). Reuniu-se 23 pacientes com DAOMS unilateral, no grupo 1. Sete pacientes, sem DAOMS foram selecionados como o grupo controle (grupo 2). Os membros testados sem DAOMS do grupo 1 e do grupo 2 não apresentaram diferença estatística. A comparação de cada membro dos pacientes do grupo 1, com e sem DAOMS mostrou que os membros com DAOMS apresentaram desempenho significativamente menor que os membros sem lesão. Este teste permite a avaliação objetiva da limitação causada pela DAOMS de forma segura e objetiva / The objective of this work is to present the results of a stress test using an isokinetic dynamometer in patients with occlusive arterial disease in upper limbs (OADUL). Group 1 has 23 patients with unilateral subclavian occlusive disease. Seven patients, without OADUL, were included in a control group (group 2). No statistically difference was found in all parameters studied between limbs without OADUL in groups 1 and 2. So, each arm in group 1 (with and without OADUL) were tested. For all these parameters, the SOD limbs presented significantly lower values than the control limbs. This test gives an objective grade of limitation of the muscle function in patients with OADUL

INTRODUÇÃO: A literatura tem postulado que a ventilação por pressão positiva não invasiva (VNI) pode facilitar o desmame de um grupo específico de pacientes. O objetivo deste estudo foi comparar a utilização da VNI como método alternativo na supressão da ventilação mecânica no pós-operatório de cirurgia cardíaca. MÉTODOS: Neste estudo prospectivo controlado e randomizado, foram estudados 100 pacientes submetidos a cirurgia de revascularização do miocárdio ou cirurgia valvar. Os pacientes foram admitidos na Unidade de Terapia Intensiva (UTI), sob ventilação mecânica e randomizados posteriormente em grupo estudo (n= 50), que utilizou VNI com dois níveis pressóricos após extubação, e grupo controle (n= 50), que utilizou a técnica convencional de supressão da ventilação mecânica. Foram analisados os tempos correspondentes à anestesia, cirurgia, circulação extracorpórea e ventilação mecânica na UTI. As variáveis gasométricas, hemodinâmicas e radiológicas foram avaliadas antes e após a extubação. RESULTADOS: Os grupos controle e estudo apresentaram comportamento semelhante quanto ao tempo de desmame ventilatório e as outras variáveis estudadas não apresentaram diferença estatística. A utilização da VNI por 30\' após a extubação, nos pacientes com atelectasias, promoveu diferença significativa na PaCO2 no grupo coronariano e na PaO2 no grupo submetido à cirurgia valvar. CONCLUSÃO: O tempo para supressão da ventilação mecânica foi similar nos grupos. Fatores extrísecos interferiram na evolução do desmame. O uso da VNI por 30 minutos após extubação apresentou diferença estatisticamente significante nas variáveis gasométricas em pacientes com atelectasias / INTRODUCTION: It was postulated that noninvasive positive pressure ventilation (NPPV) could facilitate ventilatory weaning in specific patients. The aim was to compare NPPV as alternative ventilatory weaning method with a standard ventilatory weaning protocol in the immediate postoperative period of cardiac surgery. METHODS: One hundred consecutive patients submitted to coronary artery bypass grafting or valvar surgery were addmitted in the Intensive Care Unit (ICU) and mechanicanically ventilated. They were randomly assigned to a study group (n=50) wich use NPPV witn bilevel presssure in the airways and a control group (n=50) witch used the conventional weaning thecnique. The outcome measures were anestesie, surgery, cardiopulmonar bypass and mechanical ventilation time. Arterial blood gases, hemodynamics and chest X-rays were assessed pre and post extubation. RESULTS: Weaning times were similar in both groups, and no differences were found in the studied variables. There were statistic significance considering PaCO2 in coronary and PaO2 in valvar group using NPPV 30\' after extubation, when atelectasis was detected. CONCLUSION: The ventilatory weaning time was similar in both groups. Extrinsics factors had interfered in weaning evolution. NPPV use during 30\' after extubation had statistical significance in gasometric variables in patients with athelectasis

Objetivos: Analisar a frequência de falha da extubação em recém-nascidos pré-termo em ventilação mecânica convencional após a extubação traqueal nos grupos submetidos a ventilação por pressão positiva intermitente por via nasal (nIPPV) e pressão positiva contínua em vias aéreas (nCPAP). Métodos: Foram estudados 72 recém-nascidos pré-termo portadores de insuficiência respiratória, com idade gestacional 750 gramas, que necessitaram de entubação traqueal e ventilação mecânica. Após terem preenchido os critérios de extubação, os recém-nascidos foram submetidos a nIPPV (n=36) ou nCPAP (n=36) de acordo com o resultado da randomização. Os parâmetros iniciais para os RN randomizados para nIPPV foram: FR = 12 ipm; PIP = 16 cm H20; PEEP= 6 cm H20; FiO2 ? 40%, e para aqueles randomizados para nCPAP foram P=6 cm H2O; FiO2 < 40%. O estudo foi finalizado após um tempo de extubação de 72 horas ou quando o RN preenchesse os critérios de falha na extubação. O projeto de pesquisa foi aprovado pela Comissão de Ética de ambos os Serviços. Resultados: A grande maioria dos RN recebeu pelo menos uma dose de surfactante exógeno (80,5% no grupo nIPPV e 83,3% no grupo nCPAP, P= 1). O tempo médio de permanência em ventilação mecânica também foi semelhante (6,2 e 7,3 dias, P= 0,59, respectivamente). Entre os 36 RN randomizados para nIPPV, 6 (16,6%) apresentaram falha de extubação em comparação a 11 (30,5%) dos 36 RN randomizados para nCPAP. Apesar de se ter observado redução relativa de risco de falha de extubação da ordem de 45% (IC 95%: 0,23 a 1,32) a favor da nIPPV, esta diferença não alcançou significância estatística. Constatamos uma chance de falha de extubação de 4,38 vezes no grupo nCPAP quando comparado ao grupo nIPPV após excluírmos os RN com peso de nascimento inferior a 1000 gramas, sendo esta diferença estatisticamente significativa (P= 0,045).Complicações gastrointestinais e neurológicas, além de outras complicações, não ocorreram nos recém nascidos pré-termo submetidos à nIPPV ou nCPAP após a extubação. Conclusões: Embora a distribuição de frequências de falha da extubação tenha mostrado numericamente um menor índice de falha nos RNPT submetidos a nIPPV em relação àqueles submetidos a nCPAP, não houve diferença estatísticamente significante entre os dois modos de suporte ventilatório após a extubação. Ao excluirmos da análise os RN com peso de nascimento inferior a 1000 gramas constatamos um aumento estatisticamente significante na chance de falha no grupo nCPAP. / Objetive: To analyze the frequency of failed extubation in premature infants following mechanical ventilation placed on either nasal intermittent positive pressure ventilation (nIPPV) or nasal continuous positive airway pressure (nCPAP) after endotracheal tube removal. Methods: Seventy two premature infants with respiratory insufficiency and gestacional age 750 grams, who needed endotracheal intubation and mechanical ventilation were studied. Once the babies reached the criteria for exubation, they were randomized to either nIPPV (n=36) or to nCPAP (n=36) in accordance with the randomization resulted. The inicial settings for those randomized to nIPPV were: rate=12; PIP=16 cm H20; PEEP=6 cm H20; FiO2 < 40%, and for those randomized to nCPAP were P=6 cm H2O; FiO2 < 40%. The study ended after 72 hours or when the infants reached the criteria of failure of the extubation. Ethical Approval was obtained from the Hospital. Results: Most received at least one dose of exogenous surfactant (80,5% in the nIPPV group and 83,3% in the nCPAP group, P= 1). The average time of mechanical ventilation also was similar (6.2 and 7.3 days respectively, P= 0.59). Of the 36 infants randomized to nIPPV, six (16,6%) failed extubation in comparison to 11 (30,5%) of the 36 newborn randomized to nCPAP. Although to have itself observed relative reduction of risk failure of extubation the order of 45% (95%CI: 0,23 to 1,32) in the group nIPPV, this difference did not reach significance statistics. We verified a increaset of failure extubation of 4,38 times in the nCPAP group when compared to the group nIPPV after excluded premature infant from birthweight less than 1000 grams, this difference was significant (P = 0,045). Gastrointestinal and neurological complications, beyond other complications, had no occurred in premature infants submitted to nIPPV or nCPAP after the extubation. Conclusions: Although the distribution of frequencies has numerically shown a lesser index of failure in premature infants submitted to nIPPV in relation to those submitted to nCPAP after extubation they did not have statistical significance difference between the two ways of ventilatory support. To the excluded of the analysis premature infant with birthweight less than 1000 grams, verified an increase significant in the failure extubation in the nCPAP.group .

A opção por sistemas biológicos prevalece para o tratamento do esgoto sanitário. Nas décadas recentes, sistemas que possuem regiões e/ou zonas anaeróbia, anóxica e aeróbia têm-se mostrado como alternativas atraentes para remoção simultânea de matéria orgânica, nitrogênio e fósforo. No entanto, os aspectos operacionais ainda merecem ser objeto de estudo para alcançar desempenho otimizado. Nesse cenário, com intuito de comparar alternativas para a operação das unidades de tratamento de esgoto, o presente trabalho propôs-se a estudar estratégias operacionais associadas ao monitoramento, em tempo real, sem adição de fonte externa de carbono, para um reator aerado não compartimentado com crescimento suspenso e fluxo contínuo precedido de reator anaeróbio. O sistema experimental, em escala de bancada, era constituído de um reator anaeróbio, com volume útil de 43,54 L, e reator aerado, com volume útil de 68,07 L; sendo que este era formado por sete setores, em série, sem separação física. O estudo foi dividido em duas etapas: I - estudo da variação dos volumes da região aerada e da não aerada; II - estudo da aeração intermitente com ciclo de aeração/agitação pré-fixado e controlado em tempo real por sistema informatizado. Em todas as Etapas do estudo ocorreu elevada remoção de DBO e conversão de NTK para nitrato, contudo não se conseguiu obter desnitrificação em nível desejado. O uso de reatores com setores sequenciais sem divisão física (Etapa I) dificultou a obtenção de regiões distintas predominantemente anóxica e aeróbia, comprometendo a remoção de nitrogênio (principalmente a desnitrificação). A maior eficiência média de remoção de nitrogênio alcançada no reator aerado foi de 35,6% (Etapa II), quando o reator era operado com aeração intermitente sendo o ciclo de aeração/agitação controlado em tempo real. A estratégia de operação com aeração intermitente, estudada na Etapa II, favoreceu a remoção de nitrogênio. A aeração intermitente demonstrou ser uma opção promissora comparada à aeração contínua em setores específicos do reator. O controle automatizado e informatizado em tempo real dos ciclos de aeração/agitação pode ser aplicado no aperfeiçoamento da operação dos sistemas de tratamento de esgoto sanitário. / The option of biological systems prevails for the treatment of sewage waste and in recent decades, systems that have anaerobic, anoxic, aerobic regions and / or zones have proven attractive for simultaneous removal of organic matter, nitrogen and phosphorus. However, the operational aspects still deserve to be studied in order to achieve the optimized performance of these systems. In this scenario, in order to compare alternatives for the operation of sewage treatment plants, the present work aimed to study operational strategies associated with monitoring, in real time, without the addition of external carbon source, for a non-compartmentalized aerated reactor with growth suspended and continuous flow preceded by anaerobic reactor. The experimental system in bench scale consisted of an anaerobic reactor, with a volume of 43.54 L and an aerated reactor, with a volume of 68.07 L; consisting of seven sectors, in series, without physical separation. The study was divided into two stages: I - study of the variation of the volume of the aerated and non-aerated regions; II - study of intermittent aeration with cycle of aeration/agitation controlled by a pre-fixed time interval; and controlled in real time by a computerized system. In all Stages of the study high BOD removal and conversion of TKN to nitrate occurred, but were unable to obtain denitrification at desired level. The use of reactors with sequential sectors without physical division (Stage I) made it difficult to obtain predominantly distinct anoxic and aerobic regions, compromising the removal of nitrogen (mainly the denitrification). The highest average removal efficiency of nitrogen attained in aerated reactor was 35.6% when the reactor was operated with intermittent aeration with aeration cycle controlled in real time. The operation strategy with intermittent aeration, studied in Stage II, favored the removal of nitrogen. The intermittent aeration proved to be a promising option compared to continuous aeration in specific sectors of the reactor. The automated and computerized control in real-time of the aeration / agitation cycles can be applied in improving the operation of sewage waste treatment systems.